Midnight
Roma Tomato

This unique purple-skinned, high-antioxidant sauce tomato was developed by Oregon State University breeder Dr. Jim Myers. Jim has devoted years to breeding tomatoes for purple anthocyanins, hoping to explore the antioxidant potential of these pigments and their impact on human health. (Anthocyanins are the same compounds that give blueberries their color and antioxidant properties.) With this new variety, Myers brought the high anthocyanin trait into a plum (aka paste) tomato, the purple-pigmented skin encasing a deep red flesh ideal for processing and sauce applications. 

 

In the rows, it will stop you in your tracks. In the kitchen, this purple wonder shines for its quick cook time and memorable flavor, producing sauces and pastes with layers of sweetness, acidity and rich umami. 

 

Jim’s interest in breeding tomatoes for increased nutrition dates back to when he first joined Oregon State University’s breeding program in 1996. But it was Carl Jones, a graduate student and collaborator at OSU, who helped give shape to those ambitions.

 

While exploring the C.M. Rick Tomato Genetics Resource Center collection at UC Davis, Carl noticed purple-colored tomatoes containing wild genetics from the Galapagos Islands and Chile. Carl and Jim confirmed that the unique coloration derived from anthocyanins, a nutrition pigment in the skin absent from commercial tomatoes at the time. (The black and purple coloration of varieties like Cherokee Purple comes from pheophytin, another pigment.) Together, they identified how to select for a full expression of anthocyanins in the fruit, culminating in the release of Indigo Rose in 2012. 

 

The success of Indigo Rose inspired Jim to explore new expressions of this trait. Jim turned his attention to the Oregon Star, a dual-purpose slicer and paste tomato developed for Oregon’s cool climate by his predecessor, James Baggett. The resulting cross between the two varieties brought new variation that pushed the bounds of the familiar. As he made selections in the field, Jim was drawn to the appearance of what is now the Midnight Roma. It’s ovular shape signaled its use as a paste tomato (though it serves as a tasty slicer as well); but its color spoke to new possibilities in flavor and nutrition. 

 

Jim acknowledges the contributions of many other graduate students and technicians who supported the project over the years, including Peter Mes, Peter Boches, Deborah Kean, Shinji Kawai and Joel Davis. We are also grateful to the members of our chef and grower community who trialed the Midnight Roma over multiple seasons, exploring its applications in the field and the kitchen.

Days to Maturity

80 days from transplant 

 

Appearance

3-4” deep purple-red fruit. Purple color increases with direct sun exposure. 

 

Field Notes

— Semi-determinate

— Thrives in the Pacific Northwest

— Soil Requirements: Fertile, well-drained soils with an optimal pH of 6.5. Little to no additional fertilization needed. Avoid high nitrogen prior to flowering, as it will delay fruiting. Phosphorus and calcium will boost yields and prevent blossom end rot.

— Plant Support: Provide trellising or other support for ease of maintenance and harvest.

— Purple color increases with direct sun; consider plant maintenance to increase exposure.  

 

Spacing After Transplanting

— Plant spacing: 12-24”

— Row spacing: 3’  

 

Transplanting

— Sow seeds indoors 5-6 weeks before transplanting. Sow seeds ¼” deep in trays or shallow flats, 4 seeds per inch.

— Germinate on a heat mat for 7+ days (optimal soil temperature: 75-85 ̊F). Maintain consistent moisture. 

— At true leaf stage (4 weeks), bump up to 2"-cell trays or 4" pots; bury 2⁄3 of the stem to encourage adventitious root growth. Maintain temperatures at 60-70˚F. 

— Move transplants outdoors to harden off gradually for 3-5 days, protecting seedlings from wind, strong sun, hard rain and cold.

— Transplant outdoors after risk of frost has passed, when soil temperatures do not dip below 55 ̊F. 

 

Direct Seeding

Not recommended

 

Container Growing

— Transplant seedlings into 3- to 5-gallon container after risk of frost has passed, when soil temperatures do not dip below 55 ̊F. 

— Stake the plant or use a tomato cage for support. 

— Water regularly. Add supplemental organic fertilizers when plants begin to bloom.

 

Pest + Disease Information 

— Insect Pests: Monitor carefully for aphids, flea beetles and whiteflies on seedlings. Control insect pests with biological control or organic insecticide such as pyrethrin, spinosad, soaps, etc. as appropriate. Tomato hornworms (using a blacklight at night is helpful) and potato beetles can also be managed by consistent monitoring and handpicking. 

— Diseases: Use best management practices such as drip irrigation and moisture management, crop rotation, removal of post-harvest crop debris and proper air circulation to prevent common tomato diseases. Be careful not to use tobacco prior to handling plants. Properly timed use of organic fungicides can help combat infection.

 

Harvest

Harvest when the red and purple colors deepen and the fruit give slightly when gently squeezed. 

 

Storage

Store whole and dry at 45-60˚F in an open container for up to one week.